Coolant Leak

[Uncle Hud]

You got that radiator cap on right-side up and aligned properly -- not backwards, right?

Jeez, dude. Your bike should retire on disability.

 

[Bill Lumberg]

Joke well taken. It overheated today on the way home in Ga400 traffic. Momentarily. I think it's simply not holding pressure in the cooling system. I bought a new cap. If that doesn't do it, it's sprung a leak somewhere else. It's not losing a visible amount of coolant as judged by the overflow, and we're talking about weeks of commuting that all involve some stop-and-go traffic. When I'm not working long hours and have time to let the bike cool and switch caps, We'll see. You notice how I don't complain nearly as much on a f-d up problem I can manage, as I do when it's a problem that means I can't ride. For anyone who doesn't know, I maintain my bikes meticulously and ride them (tragically) within their limits. When you ride 340 plus days a year (barring breakdown or travel for the job) it's not about rain or varnish. Every day grit and grime is introduced between any two parts that move together. I've just had a little bit of rare bad luck in 2016, which is hopefully mostly in the rear view mirrors.

 

[Bill Lumberg]

I looked at a schematic this morning with a different mechanic. He thinks there's coolanty-stuff that could easily have been bumped or dislodged during the throttle body install. I'm going to fund a limited exploratory session.

 

[Fred W]

To rehash your current situation (as I understand it, correct me if I'm wrong):

You occasionally smell coolant, and the dash intermittently indicates an overheat condition, but you do not seem to be losing coolant based on the level in the overflow tank.

Smelling coolant is normal any time the engine heats up enough for the coolant to expand inside the engine and overflow into the tank. That is a normal occurrence and is what the tank is there for. If you were gushing coolant on the ground that would be a completely different situation, but you are not or your tank level would be dropping.

So the primary indicator of a problem is that the dash says you are overtemp. Couldn't this all just be a coolant temp sensor issue?

 

[Bill Lumberg]

In 30,000 miles I never smelled coolant or had the bike overheat. Now, sometimes if I'm sitting stationary for a long period, the bikes temp will climb until the fans come on, and will keep climbing until it reaches 250F or so, around which time it switches to Hi and I shut it down if I'm not already moving. I smell coolant during these times. Never otherwise.

 

[Constant Mesh]

50/50 coolant boils at 223 degF at atmospheric pressure. The fans should start at 221 degF.

With the increased pressure from the radiator cap this coolant boils at approximately 265 degF.

So if you're seeing temps above 223 the cap is pressurizing the system to some extent.

On my '04 the temp indicator should start flashing at 248 degF.

You should have the cap pressure tested to see where it begins to open.

You might also run your finger around the rim of the opening in the radiator where the cap's spring-loaded seal touches down to see if it's smooth and capable of making a good seal.

 

[Fred W]

In 30,000 miles I never smelled coolant or had the bike overheat. Now, sometimes if I'm sitting stationary for a long period, the bikes temp will climb until the fans come on, and will keep climbing until it reaches 250F or so, around which time it switches to Hi and I shut it down if I'm not already moving. I smell coolant during these times. Never otherwise.

Ah, OK. So in addition to the over-temp indication on the dash, the coolant temperature continues to climb (especially when stationary or moving slowly) even after the fan comes on, but not when the bike is moving, right? It should not do that. Very soon after the fan comes on you should see the coolant temp start to drop

This tells us that the radiator is capable of removing the heat (since it's OK when moving down the road), but that the fan is not moving enough air through the radiator. I know earlier you indicated the fan is blowing (hard), but is it pulling air through the radiator or is it just picking up air from the back side of the radiator and blowing that out the back?

I would suggest doing a side by side comparison with another FJR to be sure. Make sure the fan is running the same speed and you are getting as much air pulled through the radiator core. Feel for air being pulled in the front side of the radiator. It could just be some sort of build up on your radiator in the small area that the fan pulls air through?

edit - A good way to gauge the air suction is to hold a piece of paper or cardboard in front of the radiator when the fans are on and feel how much pull there is. You could just turn them on in the diags menu instead of overheating your engine.

 

[Bill Lumberg]

Fans run like gangbusters. No buildup at radiator. Whatever happened happened between the time I dropped the bike off and the time I picked it up (throttle body replacement).

 

[rbentnail]

Fans run like gangbusters. No buildup at radiator. Whatever happened happened between the time I dropped the bike off and the time I picked it up (throttle body replacement).

Pure speculation since I have no idea what is done to prep for a throttle body replacement but if the coolant pipe/hoses at the top on the engine were fiddled with it is possible to easily kink the big hose running down from the pipe on the left side. Please DAMHIK this.

 

[Fred W]

Fans run like gangbusters. No buildup at radiator. Whatever happened happened between the time I dropped the bike off and the time I picked it up (throttle body replacement).

The fans can be "running like gangbusters" and still not pulling enough air through the radiator. Did you feel for air suction at the front of the radiator?

 

[Bill Lumberg]

I do feel it on both sides Fred. I'm wondering if a hose didn't get pinched or incorrectly reattached in the process.

 

[Uncle Hud]

PM or call me if you want to do a side-by-side temperature experiment. Working a GT golf tournament this weekend, but can be available during the week.

 

[Fred W]

I'm wondering if a hose didn't get pinched or incorrectly reattached in the process.

While that is plausible since they were messing around under the tank, the one reason that I wouldn't think the problem was lack of coolant flow is that you said the temperature is normal when riding down the road. It seems to me that if the hoses were pinched restricting coolant flow the engine would overheat all of the time.

 

[Constant Mesh]

Is your engine running too lean since the throttle body change? Supposedly if it runs too lean it runs too hot.

Can the oxygen sensor have any effect while idling?

Maybe you have excess heat that the fans can't overcome when sitting still?

Maybe something's out of whack with one of the fuel management sensors -- intake air pressure sensor, atmospheric pressure sensor, intake air temperature sensor, coolant temp sensor, or oxygen sensor.

They obviously had to manipulate the the pressure sensors and intake air temp sensor in the throttle body swap.

It would seem more likely that they could have affected one of these inputs rather than the cooling system.

 

[hppants]

Bill - what does the dealer that fixed the T/B issue say? Are they on record as being notified that you believe the T/B repair has somehow caused your intermittent overheating? Have they encouraged you to continue to ride the bike, or did you make a decision to do so on your own?

Stay with me for a min...

Do you have any written records associated with your return to the dealer, and any explanation given therein? Has the dealer run a pressure test on the cooling system (connect a hand pump with a fitting that fits in place of the radiator cap, then pressurize the cooling system to Yamaha's specification, thereby simulating the pressure of the coolant during a high heat condition)? If so, were any leaks detected? Have they verified that the fans cycle at the temperatures Yamaha specifies?

At this point, it's clear that you are unable to pinpoint why this condition is occurring. And the forum, despite its very best efforts, hasn't been able to help much either. At issue here is "who" is responsible. If it's a $40.00 fix, it doesn't matter. If $4,000.00 - big problem.

If it were my bike, at this point, I would do one of two things:

1. Start taking it apart myself and investigate. I'd pull the tank and get down to where the T/B could be fixed. I'd examine the entire cooling system (eyes on) and verify all hoses routed correctly and tight. I'd then pressurize the cooling system and look over every mm of it to verify not one smidge of coolant leaking. Then, with the tank raised, I'd start the bike and let it idle until the overheating starts and see what is happening. If you are smelling coolant then, you should be able to see it. If the fans at least come on at the 225-ish temp, then we know that part is right. We can't rule out a partially closed (or malfunctioning) thermostat with any of these test. The only way to do that would be to pull the T/S, and with a thermometer, test it on top the stove.

or

2. I'd bring it back to the dealer and say "fix it and don't call me until you do". Whatever is causing the problem is real. Something is not right. When they find out what that is, either it is related to the T/B repair or it is not. Based on the marked differences between these engine systems (cooling system v/s Fuel Mgmt system), there should be no doubt as to the root cause of the issue. When that is determined, if related to the T/B, I'm sure the dealer will make it right. If by some major coincidence it is not related to the T/B repair, then at the very least you will know it is fixed. Pay the man his money and take satisfaction in your resolve.

I don't think running the FJR at 250 degrees for a very short time is going to be detrimental to the motor. However, I don't know that. Running a motorcycle with a known history of overheating problems is kind of playing with fire. If you damage the motor, regardless of the root cause or how you got there, the resolve is going to be VERY complicated. The dealer is not going to roll over and give you a $4,000.00 motor. Even though the most grenaded motor can be fixed, but the fall out from that can also be lengthy and complicated (and very expensive).

How does this logic sit with you?

 

[Bill Lumberg]

Imminently logical. Dealer and Yamaha know of the problem and that its throttle body replacement related. I have decided to discontinue service at this shop. I'm having an exploratory session with another Yamaha mechanic to see what's pinched or leaking.

 

[Fred W]

Bravo!

There has to be someone more capable around than those clowns.

 

[Canadian FJR]

Any chance that there is a small leak around the o-rings where the coolant pipe connects?

Canadian FJR

 

[bseelbach]

So I was just advised to follow this thread as I am having similar issues. 2013 91k I haven't noticed any coolant leak and overfill level stays steady but engine temp seems abnormally high for the last month or so since a valve check/coolant change at biker geeks tech day.

At highway speed and 60-80 degree ambient bike will run about 170-190 but If I get in any stop and go or city traffic, Temps climb quickly. Fans kick on around 220ish but are not enough to keep the temp from rising. If I blip the throttle temp will drop a little but I can only put a bandaid on the problem for 5 min or so at a complete stop before it jumps to dangerous levels. In the last couple of weeks I have had to get off the highway or ride the shoulder to keep airflow moving.

After I get back from SFO I plan to flush with distilled water and refill with 50/50 mix.

I hope we are not unearthing a problem here......

 

[Bill Lumberg]

Sounds just like mine, except I can go days of stop and go and never climb over 226, and then on the fourth day see a problem. I think it may be air in the system or a pinched hose. Temp is a bit higher much of the time, but not alarmingly so. Overheats if allowed, but only once in a while at a long stop. I don't let it climb to damaging levels. If it doesn't rebound once the fans go on, I shut it down. Yesterday, in traffic for 90 minutes, zero problems. Waiting until I have time for a flush and fill and look-see.